Galaxy S4 not recognized by a PC

[AC Question]

Hi,
When I connect my S4 via USB to my PC (win7) it says it is charging, but the PC does not register that the phone is connected at all.

I tried different cables (including the orginal)
I tried different PCs.
I tried USB debugging.
I tried reinstalling USB drivers.

Nothing works. And I cant even transfer files via AirDroid to my external MicroSCHD card because of the 4.4.2 restrictions.

Can you please help?
Thanks you

 

[B. Diddy]

Did you try installing the drivers from here? Download Center: Download Software, Firmware, Drivers & Manuals | Samsung